Amgen v. Sanofi is an important case, but it won’t transform patent law on its own.
By Timothy Bonis
Last April, the Supreme Court ruled in Amgen v. Sanofi, a closely watched patent case where the justices upheld the invalidation of two monoclonal antibody patents for lack of enablement. The ruling has attracted significant interest for two reasons.
First, Amgen involved genus claims in biological and chemical fields, which some experts believe the Federal Circuit has made unduly hard to obtain. This viewpoint, most prominently expressed by Mark Lemley, Sean Seymore, and Dmitry Karshtedt in The Death of The Genus Claim (2021), informed much of the debate about Amgen, although it has been challenged by scholars like Christopher Holman.
Second, Amgen dealt with monoclonal antibody patents, which now represent some of the most valuable intellectual property. (The global market for monoclonals in 2022 was $210B.) Moreover, the scope of antibody patent claims has been narrowed markedly by heightened standards for enablement and written description introduced over the past two decades; antibody inventors once received broad protection through functional claims, but the Patent and Trademark Office (PTO) has raised its requirements, partially in response to repeated invalidations of antibody genus claims at the Federal Circuit (see Chiron v. Genentech, 2004, Centocor v. Abbott, 2011, and AbbVie v. Janssen, 2014).
The decision in Amgen continues the trend of narrowing antibody patents and the perceived trend of limiting genus claims. Thus, how impactful Amgen will be on its own remains uncertain. Does it add new constraints to the patentability of antibodies, small molecules, and chemicals, or does it merely recapitulate the Federal Circuit’s previous rulings? This post reviews that debate. Part I examines how scholars and attorneys have reacted to Amgen, focusing on whether they think the case will have a legal and practical impact. Part II synthesizes these perspectives, arguing that Amgen’s direct impact will be limited. A companion piece summarizing the ruling’s significance for the industry and innovation will follow.
